Related by context. Frequent words. (Click for all words.) 74 Chicxulub 58 supercontinent 55 landmasses 55 igneous rocks 55 Paleocene 54 Valles Marineris 54 asteroid 53 lava tubes 53 stromatolites 53 spherules 52 sedimentary rock 52 hydrothermal vent 51 continental crust 51 ejecta 51 H. erectus 51 crater 51 pyroclastic flow 50 igneous rock 50 meteor 50 Saturn rings 50 WASP #b 50 volcanic crater 50 graben 50 geological formations 50 feathered dinosaurs 50 Meridiani 50 plesiosaur 49 gyre 49 Burgess Shale 49 geologically active 49 meteoroid 49 supernova explosion 49 Cascadia Subduction Zone 49 Oort Cloud 49 basaltic 49 calcite 49 geologic formation 49 polar vortex 49 lithosphere 48 basalts 48 Opportunity rover 48 Cabeus 48 Mexico Yucatan peninsula 48 Ordovician 48 foraminifera 48 geologic 48 volcanism 48 Loop Current 48 Late Cretaceous 48 Lake Vostok 48 volcanic rock 48 volcanic plume 48 oceanic crust 48 Homo floresiensis 48 Kuiper belt 47 seamount 47 volcanic vent 47 supernova remnant 47 lava flows 47 tetrapods 47 tyrannosaur 47 solar nebula 47 tar mats 47 theropods 47 magmas 47 landforms 47 marine sediments 47 eyewall 47 meteorite 47 depositional 47 stalactite 47 planetoid 47 heliosheath 47 caldera 47 comet 47 Deepwater Horizon blowout 47 olivine 47 volcanically active 47 Gliese #g 47 Paleozoic 47 hadrosaur 47 melting glacier 47 interglacial period 46 comet nucleus 46 magma chamber 46 theropod 46 Younger Dryas 46 scarps 46 landform 46 ancient Mayans 46 Gusev Crater 46 hydrothermal activity 46 Yucatan peninsula 46 Cascadia subduction zone 46 marine reptile 46 massive sulphide deposit 46 rock outcropping 46 underwater plumes 46 volcanic islands 46 rock outcrop 46 biodiversity hotspot